I found Slated for Death, set in Wales in the old slate mines that are now closed except to tourists and school groups.Though the slate industry ran for a couple centuries in north Wales, this mystery novel is set in the present time.
Slated for Death: A Penny Brannigan Mystery #6 by Elizabeth J. Duncan
Published April 14, 2015 by Minotaur
Genre: mystery set in north Wales
Teaser from the page I'm on right now: They are planning to hold the St. David's Day concert down the mine this year and Glenda was organizing it so she was on a site visit. (ch. 4)
Book description: When the body of well-liked Glenda Roberts is discovered at the bottom of a former slate mine, now a busy tourist attraction, pandemonium erupts in the North Wales town of Llanelen. Penny Brannigan finds herself drawn into the investigation .... A visit to Glenda’s mother deepens her conviction that a hidden family secret is the real reason for the murder.I'm enjoying it so far - the setting and the characters.